Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = ' <task action="4" id="941010010"> <release> <item type="cost" vitality="1" /> <item type="fight" npcid="1010010"> <win> <item type="aside" content="[color=#ff7e53]你胜利了！[/color]" auto="true" /> <item type="random"> <item probability="0.001"> <item type="reward" yueli="300" money="100" auto="true"> <item id="2801" num="1" /> </item> </item> <item probability="0.001"> <item type="reward" yueli="300" money="100" auto="true"> <item id="2901" num="1" /> </item> </item> <item probability="0.001"> <item type="reward" yueli="300" money="100" auto="true"> <item id="3001" num="1" /> </item> </item> <item probability="0.001"> <item type="reward" yueli="300" money="100" auto="true"> <item id="3101" num="1" /> </item> </item> </item> <item type="param" key="fight-1010010" action="update" value="1" /> </win> <lose> <item type="aside" content="[color=#ff7e53]你被{rnpc}打倒在地！[/color]" auto="true" /> </lose> </item> </release> </task>'; my $regex = qr/(?:\s)*<task action="4" id="94(\d\d\d)00(\d\d)">(?:\s)*<release>(?:\s)*<item type="cost" vitality="\d"(?:\s)*\/>((?:\n|.)*?)<item type="param(?:(?:\n|.)*?)(?=<\/win)((?:\n|.)*?)<\/release>(?:\s)*<\/task>(?:\s)*/mp; my $subst = '\\n\\n\\n\\n<stroy id="$17$2" areaid="0" startid="-1" endid="-1" maxnum=\'0\' interval=\'0\' count="0" type=\'3\'>$3$4</stroy>\\n\\n'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html